Conventionally, global environmental problems such as a global warming are recognized. In place of a car using fossil fuel such as gasoline that exhausts carbon dioxide which causes global warming, recently, a vehicle such as an electric vehicle that uses the fuel cell is noted.
As such a fuel cell system, the fuel cell system, of which a schematic diagram is shown in outline in FIG. 27, is adopted.
That is, fuel cell system 100 of FIG. 27 includes fuel cell stack 102 that is the main body of the solid polymer type fuel cell.
In this fuel cell stack 102, an anode 106 (hydrogen pole), in which the hydrogen gas that is the fuel gas is supplied from hydrogen tank 104 that is the fuel gas supply source, is provided. Moreover, in the fuel cell stack 102, a cathode (air pole) 110, in which an air that is the oxidant gas is supplied through compressor 108, is provided.
The hydrogen gas, that is the fuel gas, is stored, as a high-pressure hydrogen gas, in a hydrogen tank 104. The high-pressure hydrogen gas supplied from hydrogen tank 104 is decompressed to the driving pressure of the fuel cell by a hydrogen pressure adjustment valve 112. The high-pressure hydrogen gas is supplied to the anode 106 through a hydrogen supply passage 114.
The surplus hydrogen gas, which is not consumed by the anode 106, is returned to the hydrogen supply passage 114 by a hydrogen circulation passage 118 through a hydrogen circulation pump 116. The surplus hydrogen gas is mixed with the hydrogen gas which is supplied from the hydrogen tank 104, and is supplied to the anode 106.
On the other hand, air as the oxidant gas is compressed through a compressor 108 through the air filter not shown in the figure, and the compressed air is supplied to the cathode 110 through an air supply passage 120.
In addition, oxygen in the air is used to react at the cathode 110, and the remaining air is exhausted through an air pressure adjustment valve 122 that adjusts the air pressure.
Moreover, in the fuel cell stack 102, in order to keep the temperature of the fuel cell stack 102 at the predetermined temperature, the cooling system, in which the cooling fluid such as cooling water is circulated around, is provided. That is, the cooling fluid cooled down with radiator 124 is circulated to cool the fuel cell stack 102 through a cooling water circulation path 128, 130 by a cooling water pump 126.
Moreover, in the hydrogen circulation passage 118, a discharge path 132 is diverged to exhaust to the outside the nitrogen gas and the like included in the surplus hydrogen gas. For instance, a purge valve 134 for opening and shutting this discharge path 132 with an electromagnetic valve is disposed.
By the way, since impurities such as foreign matter may be contained in the fluid that flows in the hydrogen circulation passage 118, the filter is provided in the purge valve 134 in the discharge path 132.
For example, there is Patent Literature 1 (JP, 2008-270151, A) as a fuel cell system that disposes a filter in the purge valve 134 on such a discharge path 132.